the true value in decimal part, the square root approximation of Labban gave slightly lower value, the integer part are the same. Sexagesimal arithmetics Multiplication The Hindu sexagesimal multiplication format was completely different from Hindu decimal arithmetics. Kushyar ibn Labban's example of 25 degree 42 minutes multiplied by 18 degrees 36 minutes was written vertically as 18| |25 36| |42 with a blank space in between Influence Kushyar ibn Labban's Principles of Hindu Reckoning exerted strong influence on later Arabic algorists. His student al-Nasawi followed his teacher's method. Algorist of the 13th century, Jordanus de Nemore's work was influenced by al-Nasawi. As late as 16th century, ibn Labban's name was still mentioned. References External links The Development of Hindu-Arabic and Traditional Chinese Arithmetic, Chinese Science 13 1996, 35-54 Indian mathematics Hindu Reckoning,Principles of